1. Field of the Invention
The present invention relates generally to sailing vessels, and more particularly to unique designs for aerodynamic wingsails having lightweight sail clothes, support members, mast features, hardware assemblies, as well as operation and control components.
2. Description of the Prior Art
Since their invention over thousands of years ago, sailboats have evolved in a multitude of fascinating ways. Many of the design advances made during that time were practical in nature, such as improving safety and simplifying operation, while others were made specifically to increase boat speed. For example, the recently developed rigid wingsails used on the America's Cup catamarans have only increased speed, while compromising simplicity and safety.
U.S. Pat. No. 6,892,660 is entitled Furling Sail and Means For Turning Mast, and discloses a furling sail and particular hardware/ball bearing assembly for turning the mast. The sail is described as to be fully battened by several thin, spaced apart battens which are positioned about steep angles to the sail. The battens are made of fiberglass rods which are held in place by cord and threaded through a batten. The lower ends of the battens are free to rotate inside pockets. This patent teaches the use of a rotating mast and diagonal battens to improve the functionality of a sail. In contrast, the instant inventive wingsail is supported by rotating brackets on a mast that does not rotate. The '660 patent incorporates an A-frame to support the upper mast bearing, functioning as a fixed base supporting the mast. The inventive wingsail herein utilizes two movable struts to form a tilting triangular base that supports the mast.
U.S. Pat. No. 5,619,946 is entitled Sail Furling Device With Bearings To Permit Simultaneous Cable And Extrusion Rotation, and illustrates a furling device and a particular upper and lower bearing assembly which compensate for static and horizontal loads, and rotates both the luff extrusion and the sail cable wire.
U.S. Pat. No. 4,699,073 is entitled Spaced Double Surface Sail Constructions, and relates to a spaced double surface sail construction wherein a sail envelope has an inner open area between two spaced sail surfaces. The sail surfaces have spaced battens, and battens support strips support, space, and guide the center portion of the battens. A batten socket support strip supports and spaces the batten sockets along the mast, and permitting pivotal movement. This wingsail has battens that pivot on the mast and are moved from side to side within the wingsail surface and camber is only reversible, not adjustable.
U.S. Pat. No. 4,064,821 is entitled Variable Camber Wing Sail, which describes a wing sail having a variable camber and having a two (2) sided spaced apart sail structure, including a plurality of resiliently deformable struts for each side. The beam produces a cam action to bend the struts producing an airfoil configuration. The design utilizes dual sliding tracks on rotating masts supporting twin sails that form thick wingsail profiles. Unlike the inventive wingsail, the masts are the leading edges of these wingsails, and include a variable camber control device consisting of a rigid boom and two pulleys connected to a bracket on the mast that also supports flexible battens that extend from the mast to the trailing edge of the surface. In contrast, the battens in the inventive wingsail surround the mast, forming the leading edge of the surface forward of the mast.
However, none of the above-referenced patents or the prior art address the designs, components and/or operation of the instant aerodynamic wingsail, which constitutes a substantial improvement over the art. Furthering previous wingsail concepts, the invention described below combines the superior aerodynamic efficiency of wingsails with the safety and simplicity of the best modern technology, thereby creating a useful and beneficial advance in sailboat evolution.
It is therefore an objective of the present invention to provide an improved lightweight wingsail and vessel with custom designed components providing for superior aerodynamic performance.
It is yet another objective of the present invention to provide an improved lightweight wingsail and vessel which eliminates problems with prior designs and provides enhanced benefits for operation and control.
Finally, it is an objective of the present invention to provide to provide an improved lightweight wingsail and vessel which is cost effective and operationally efficient while incorporating the above mentioned objects and features.